The present invention relates generally to flexible panels of construction used for roll-up doors and flexible links connecting to adjacent railroad car sections together. More specifically, the present invention relates to flexible panels that are resistant to cutting and puncturing.
Durable, flexible panels are known. Such panels are incorporated into roll-up doors which are typically fabricated from flexible fabric or pivotally connected horizontal metal slats. The roll-up doors fabricated from flexible fabric are undesirable because they are not sufficiently cut-proof or puncture-proof and therefore are susceptible to vandalism.
While the doors made from connected horizontal slats are sufficiently strong, they are relatively expensive to manufacture because of the difficulty in assembling the interconnected horizontal slots. Further, the roll-up doors made from connected horizontal slats are flexible in a horizontal direction only so they can be rolled up onto a horizontal roll disposed at the top of the door opening. However, these types of roll-up doors are not flexible in a direction that extends outward or inward from the plane of the door. Therefore, these doors are not flexible if an automobile or other structure bumps or engages the door when the door is closed. Often, the metal slots become bent which makes it difficult to extend and retract the door. Further, when one or more of the horizontal slats of the door are sufficiently bent, the entire door or curtain must be replaced.
Another use for a strong material for connecting purposes are vestibule connections for adjoining ends of two railroad car sections. Currently, such vestibule connections are fabricated from accordion-like structures that are a combination of metal frames connected by a webbing that is fabricated from rubber or a combination of rubber and durable fabric. Also, the accordion-like connecting structures can be fabricated entirely from metal.
The currently available vestibule connections suffer from a number of deficiencies. First, if rubber or a fabric material is used to connect the frame components together, the rubber combination of rubber and fabric can be easily cut or damaged by vandals. This is particularly problematic for trains that are transporting valuable commodities, such as luxury automobiles. Typically, in railroad car sections designed exclusively to transport automobiles, the vestibule connection or flexible connection between the railroad cars is the only means of preventing unauthorized entry into the car sections themselves. Accordingly, by fabricating the vestibule connections from rubber or a combination of rubber and fabric, the vestibule connections and therefore the car sections themselves are susceptible to vandalism and unauthorized entry.
Another disadvantage associated with currently available vestibule connections is reliance upon the use of metal frame members in the accordion-like structure. Any damage to these metal frame members often requires replacement of the entire vestibule connection.
Accordingly, there is a need for an improved flexible and very strong material that is resistant to cutting and puncturing. Such an improved material will lead to improved roll-up type doors as well as to improved vestibule connections or covered connections for adjacent railroad car sections. It is also anticipated that such an improved flexible and durable material would have many other applications as well.
The present invention satisfies the afore-noted needs by providing an improved, flexible and vandal-resistant panel that is fabricated from a flexible metallic skeleton structure such as woven steel wire cloth, woven stainless steel wire cloth, wire belt material or metallic chain link structures, that is embedded in a layer of polymer material such as natural rubber, synthetic rubber, polyvinyl chloride, polyurethane or other polymer materials.
In an embodiment, the flexible metallic structure comprises a chain link structure comprising a plurality of parallel and adjacent links that are interconnected by a plurality of cross-members. Each link is generally in the form of a triangular wave with linear link elements interconnected to one another at transverse arcuate folds. The folds are disposed alternately on opposed first and second sides of each link. Each cross-member is a generally linear strand nested between link elements along a first side of one link and a second side of an adjacent link.
In an embodiment, the polymer is natural rubber.
In an embodiment, the polymer is synthetic rubber.
In an embodiment, the polymer is polyvinyl chloride.
In an embodiment, the polymer is polyurethane.
In an embodiment, the polymer is neoprene.
In an embodiment, the flexible panel of the present invention is incorporated into a roll-up door that comprises a flexible panel made in accordance with the present invention and which has an upper end and a lower end. The upper end is connected to a shaft which, in turn is connected to a pulley mechanism. The pulley mechanism rotates the shaft in a first direction by winding the panel around the shaft and raising the lower end of the panel and the pulley mechanism further rotates the shaft in a second direction for unwinding the panel from the shaft to lower the lower end of the panel.
In an embodiment, a plurality of flexible panels made in accordance with the present invention are used to link two adjacent railroad car sections. Each car section has an end disposed between a first side and a second side as well as a top. The two car sections are spaced apart by a first distance.
In an embodiment, a first side panel is used to link the first sides of the two adjacent car sections. The panel is made in accordance with the present invention as described above. The first panel also has a length that is greater than the first distance thereby providing sufficient slack when the train turns in a direction away from the first sides of the two adjacent car sections. Similarly, a second panel made in accordance with the present invention as described above is used to link the second sides of the adjacent car sections. Again, the second panel has a length that is greater than the first distance which provides sufficient slack when the train turns in a direction away from the second sides of the two adjacent car sections. A top panel, also made in accordance with the present invention, is used to link the tops of the adjacent car sections. Preferably, the top panel also is provided with sufficient slack for turning. As a result, three panels are used to couple or link two adjacent railroad car sections. The panels are strong, durable and cut-proof thereby providing the requisite resistance to vandalism.
In an embodiment, the vestibule connection provided by the present invention includes a top panel and opposing first and second side panels as discussed above. However, the top panel is linked to the first and second opposing side panels by a plurality of shingled sections that are connected together in an end-to-end fashion.
In an embodiment, the top panel and first and second opposing side panels each include an accordion-like or corrugated structure to provide the slack that is necessary when the train turns.
In an embodiment, the shingled sections have an accordion-like structure to provide the necessary slack between two adjoining car sections.
In an embodiment, the present invention provides a method of fabricating a flexible and vandal-resistant panel. The method comprises the steps of providing a plurality of links, each link including a plurality of linear link elements interconnected by transverse arcuate folds disposed alternately on opposite sides of the link. The method also comprises the step of providing a plurality of generally linear cross-members and connecting a first side of each link to a second side of a preceding link by inserting a cross-member between the links so that the cross-member extends between link elements through the arcuate folds disposed along the first side of each link and the second side of the preceding link. Further, the method includes the steps of connecting the second side of each link to a first side of a succeeding link by inserting a cross-member between the links so that the cross-member extends through the arcuate folds disposed along the second side of said each link and the first side of the succeeding link. Finally, the method includes the steps of embedding the connected links or chain link structure in a layer of polymer material.
It is therefore an advantage of the present invention to provide an improved flexible panel which is cut-proof and vandalism-resistant.
Another advantage of the present invention is that it provides an improved flexible panel that cannot be dented.
Yet another advantage of the present invention is that it provides an improved vandalism-proof connecting vestibule for adjacent railroad car sections.
Yet another advantage of the present invention is that it provides an improved curtain for a roll-up door which is vandalism-resistant and which cannot be dented during use.
Still another advantage of the present invention is that it provides an improved method of fabricating flexible, cut-proof and vandalism-resistant panels or curtains.